Pollen vigor of Schima superba under different storage conditions

Objective This study aims to explore the optimal preservation conditions of Schima superba pollen and construct an efficient perservation system to maintain its vigor.

Method In this study, 9-year-old S. superba individual plants were used as the research object, and pollen collection was carried out at different flowering stages. The changes of pollen vigor under different collection time, pollen vigor detection methods and different storage conditions were analyzed.

Result The flower branches at different flower bud stages were hydroponically cultured. The flowers bloomed on the first day had higher pollen vigor and no significant difference. It was appropriate to collect pollen from 10:00 to 12:00 in the morning. The TTC staining method was the most suitable for rapid identification of S. superba pollen vigor, and the in vitro germination method was more accurate. The pollen germination effect was the best when the in vitro germination medium was 0.1 g·L⁻¹ H₃BO₃ + 100 g·L⁻¹ sucrose. At the same storage time, reducing the storage temperature effectively slowed down the decline rate of pollen vigor, and different temperatures had a significant effect on the pollen vigor. When short-term storage was required, the low temperature condition of 4 ℃ could ensure that the pollen maintained its vigor within one month and complete the cross-pollination work of the current year. For long-term storage of pollen, at the low temperature conditions of −20 and −80 ℃ were more effective.

Conclusion The results of this study not only provide a scientific basis for the collection and storage of S. superba pollen, but also provide a reference for solving the problem of artificial hybridization breeding caused by inconsistent flowering periods in seed orchards.